As for me, seeker after truth and student of life as I am, I shall take care not to follow their example. I take from life the movements I observe, but it is not I who impose them.
Even when a subject which I am working on compels me to ask a model for a certain fixed pose, I indicate it to him, but I carefully avoid touching him to place him in the position, for I will reproduce only what reality spontaneously offers me.
I obey Nature in everything, and I never pretend to command her. My only ambition is to be servilely faithful to her.

p. 30 - Art, 1912 - Ch. I. Realism in Art